// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GL_GL_HELPER_H_
#define UI_GL_GL_HELPER_H_

#include "ui/gl/gl_bindings.h"
#include "ui/gl/gl_export.h"

namespace gfx {

class GL_EXPORT GLHelper {
public:
    // Compiles a shader.
    // Does not check for errors, always returns shader.
    static GLuint CompileShader(GLenum type, const char* src);

    // Compiles a shader and checks for compilation errors.
    // Returns shader, 0 on failure.
    static GLuint LoadShader(GLenum type, const char* src);

    // Attaches 2 shaders and links them to a program.
    // Does not check for errors, always returns program.
    static GLuint LinkProgram(GLuint vertex_shader, GLuint fragment_shader);

    // Attaches 2 shaders, links them to a program, and checks for errors.
    // Returns program, 0 on failure.
    static GLuint SetupProgram(GLuint vertex_shader, GLuint fragment_shader);

    // Sets up a vertex buffer containing 4 vertices that can be used to draw
    // a quad as a tri-strip.
    static GLuint SetupQuadVertexBuffer();

    // Draws a quad to the currently bound frame buffer.
    static void DrawQuad(GLuint vertex_buffer);
};

} // namespace gfx

#endif // UI_GL_GL_HELPER_H_
